The purpose of this tool is to safely facilitate the servicing of the hydraulic front forks on most American V-Twin motorcycles.
The inventor having rebuilt numerous front ends to service, add chrome lowers, or tune the front end with optional springs has found the process cumbersome, frustrating, and potentially dangerous. Removing or installing the fork caps was particularly challenging posing the potential of cross threading and/or damage. This servicing also posed a safety hazard in the cap flying off as it is under spring pressure. Also noted was the potential for saving significant time in the process by using the features of this tool.
The prior art reveals several related patents. The German patent of Woitzik (DE2230670) shows a tool for setting the valve clearance for internal combustion engines. The tool combines the adjusting spanner with the locking nut spanner in a single tool to be used with two hands. It is not related to servicing of motorcycle front forks. The French patent of Nolte (FR401769) relates to a tool using a cam and a matching thread pitch on the tool to screw or unscrew a nut from a bolt. It also is not related to the servicing of motorcycle forks. Other than the use of threaded rod to apply or release pressure, Nolte (FR401769) is very complex and appears to be designed to be used in a repetitive process to apply equal pressure to fasten or remove bolts, rivets etc, as in tamper proof hardware. The cam device, interchangeable threaded sleeves, and various adapters make this expensive and cumbersome and not useful in servicing front fork tubes of a motorcycle.
The patent of Borner, Jr. (U.S. Pat. No. 5,477,598) is for a cap and spring installation and removal tool for use in servicing motorcycle forks. It has some similarities to the present invention, such as incorporating a threaded shaft and aiding in the safe removal and installation of a spring tube cap. However, Borner, Jr. uses a yoke engaging a top flange in the tube housing to function. Such a step in the spring housing to engage a tool yoke has not been a feature of conventional contemporary motorcycles for some time thereby making Mr. Borner's tool design non-functional on most of today's street motorcycles. The tool described by Borner's patent handles one fork tube at a time and has no convenient means of mounting to a bench top; it is also more expensive to manufacture and not as intuitive to use as the present invention.